1. Field of the Invention
The present invention relates to an underwater propelling apparatus. More particularly, the present invention relates to an underwater propelling apparatus used for a fishing boat, a working boat, a submarine searching boat and a submarine working boat and the like.
2. Description of the Related Art
As a conventional underwater propelling apparatus, a screw propeller 51 is used for a submarine searching boat 52, as shown in FIG. 1.
The screw propeller 51 generates a thrust only in its rotation axis direction. Thus, the directional control of the submarine searching boat 52 requires an auxiliary apparatus such as a rudder 53, a side thruster 54 and the like. Hence, the performances of the directional control and a position keeping control are limited as compared with a straight propelling performance.
Also, there may be a fear that the screw propeller 51 or the side thruster 54 catches nearby matter. Thus, a limit on usage is imposed from the viewpoint of safety.
In the case of a conventional screw propelling apparatus of a submarine searching boat, mud on the sea bottom is disturbed, making noise and disturbing the searching operation. Also, its small energy prevents long operation.
An underwater propelling apparatus is desirable for stably carrying out a propelling operation and a steering operation.
An underwater propelling apparatus is also desired for stably carrying out directional control and position keeping control.
An underwater propelling apparatus is also desired for effectively obtaining thrust.
An underwater propelling apparatus is further desired for freely carrying out not only a propelling operation, but also a steering operation.
An underwater propelling apparatus is also desired for freely carrying out directional control and position keeping control.
An underwater propelling apparatus is further desired which has an excellent silence property.
By the way, Japanese Laid Open Patent Application (JP-A-Heisei, 11-152085), in relation to the application of this applicant, discloses the following underwater running body. That is, in an underwater running body, a plurality of wings, which are vibrated by reciprocating rotations of rotation shafts fixed to a front edge, are installed in series. Then, joint control of respective rotation shafts enables the plurality of wings to be flexibly actuated like a tail fin of a fish as a whole. Thus, thrust can be obtained. In addition, a steering operation can be done by controlling a vibration center of each of the wings. Also, floating/sinking control is carried out by a water filling/draining operation for a tank.
The present invention is accomplished in view of the above mentioned problems. Therefore, an object of the present invention is to provide an underwater propelling apparatus for stably carrying out a propelling operation and a steering operation.
Another object of the present invention is to provide an underwater propelling apparatus for stably carrying out directional control and position keeping control.
Still another object of the present invention is to provide an underwater propelling apparatus for effectively obtaining thrust.
Still another object of the present invention is to provide an underwater propelling apparatus for freely carrying out not only a propelling operation but also a steering operation.
Still another object of the present invention is to provide an underwater propelling apparatus for freely carrying out directional control and position keeping control.
Still another object of the present invention is to provide an underwater propelling apparatus having an excellent silence property.
In order to achieve the objects of the present invention, an underwater propelling apparatus includes a body and a plurality of vibrating units, which are placed in parallel to each other on a rear side of the body. Each of the plurality of vibrating units vibrates repeatedly and reciprocally to produce thrust. The underwater propelling apparatus of the present invention uses a technique for controlling an elastically vibrating wing. The underwater propelling apparatus of the present invention is a submarine boat (a non-towed underwater vehicle) itself.
In this case, each of the plurality of vibrating units includes a plurality of vibrators which are placed in series and can be controlled independently of each other.
Each of the plurality of vibrators placed in series is elastic, and one vibrator positioned on a rear side from the body of the plurality of vibrators placed in series has a higher elastic modulus than that of another vibrator.
The underwater propelling apparatus is used in a propelled body that is propelled by the underwater propelling apparatus. The plurality of vibrating units are placed at locations separated from each other on a virtual line substantially orthogonal to a direction in which the propelled body is propelled.
The underwater propelling apparatus further includes a tank into and from which water can be filled and drained to control a floating/sinking state of the body and a water filling/draining control unit which controls operations of filling and draining the water into and from the tank.
The body also includes a plurality of underwater running units and a bed unit through which the plurality of underwater running units are linked to each other. The plurality of vibrating units are provided in a plurality of rear portions of the plurality of underwater running units, respectively. Each of the plurality of underwater running units and the bed unit has an outer appearance formed by a smooth curve to reduce underwater resistance.
In this case, each of the plurality of underwater running units is substantially ellipsoidal in shape such that a vertical side of each of the plurality of underwater running units is longer when being viewed from a front of each of the plurality of underwater running units and such that a horizontal side of each of the plurality of underwater running units is longer when viewed from a side of each of the plurality of underwater running units and on a flat plane of each of the plurality of underwater running units.
Also in this case, the bed unit is substantially ellipsoidal in shape such that a horizontal side of the bed unit is longer when being viewed from a side of the bed unit and the bed unit is substantially rectangular in shape such that a horizontal side of the bed unit is longer when viewed from a front of the bed unit and on a flat plane of the bed unit.
Further in this case, the underwater propelling apparatus is an submarine boat, and the plurality of underwater running units are designed such that a separation distance between the plurality of underwater running units is longer than a width dimension of a rear portion of the submarine boat.
In order to achieve another object of the present invention, an underwater propelling apparatus includes a body, a first vibrating unit placed on a rear side of the body in which a first vibrator vibrated by reciprocating rotation of a first rotation shaft and a second vibrator vibrated by reciprocating rotation of a second rotation shaft are arranged in series and a second vibrating unit that is placed on the rear side of the body and placed in parallel to the first vibrating unit in a horizontal direction, in which a third vibrator vibrated by reciprocating rotation of a third rotation shaft and a fourth vibrator vibrated by reciprocating rotation of a fourth rotation shaft are arranged in series. First to fourth actuators rotates the first to fourth rotation shafts, respectively. A vibrator command generator outputs a control signal to set respective amplitudes, frequencies and vibration centers of the first to fourth vibrators associated with the reciprocating rotations of the first to fourth rotation shafts and phases between the first to fourth vibrators to control the first to fourth rotation shafts jointly and respectively. An angular servo driver generates signals to control the first to fourth actuators, respectively, on the basis of the control signal.
In this case, each of the first to fourth vibrators is elastic, and the second vibrator, positioned on the rear side of the body from the first vibrators and arranged in series, has a higher elastic modulus than that of the first vibrator. The fourth vibrator is positioned on the rear side of the body from the third vibrators, is arranged in series and has a higher elastic modulus than that of the third vibrator.
The first to fourth rotation shafts are placed in a horizontal direction.
The first to fourth rotation shafts are placed in a horizontal direction such that it is possible to change a submarine depth of the underwater propelling apparatus.